Non-circular resection device and endoscope

ABSTRACT

A proximal housing for a full-thickness resection device (FTRD) is provided with a plurality of chambers through which fasteners are introduced into a portion of tissue to be resected. The proximal housing has a noncircular cut-out opposite the plurality of chambers to receive a noncircular endoscope. The proximal housing also is provided with a resection cavity into which the tissue to be resected is to be received. In addition, shaft openings are provided through which mounting shafts may be inserted. A noncircular endoscope is also disclosed for insertion into the cut-out whereby the endoscope has passages to house the functions of remote viewing, illumination, insufflation and irrigation.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates generally to a full-thicknessresection device (FTRD) for performing localized resections of lesionsin tubular organs, particularly the colon. The present invention hasparticular application to transanal and transoral surgical procedures,although it is not limited thereto.

[0003] 2. Description of the Related Art

[0004] A resection procedure involves excising a portion of an organ,approximating the surrounding tissue together to close up the holecreated by the excision, and removing the excess tissue. Variousconventional devices and procedures are available for resectioninglesions in tubular organs.

[0005] For example, several known resection devices and proceduresrequire at least one incision in an area near the portion of the organto be excised for access to the lesion or treatment site (because, forexample, the resectioning device may lack steering and/or viewingcapabilities). Thus, the incision is required to allow the physician toaccess the organ section to be excised and guide the device to thatsection. Alternatively, when the organ section to be excised is beyondthe reach of the surgical device, or the surgical device is not flexibleenough to wind through the organ to the site to be excised, an incisionwill be required to position the device for the procedure. Of course,these incisions are painful and may involve a partial or entire loss ofmobility while recuperating from the incision, in addition to recoveringfrom the tubular resectioning procedure itself. In addition, the timerequired to recover from such a procedure is often longer than forprocedures which do not require incisions.

[0006] One type of conventional resection procedure utilizes a circularstapling instrument in which a tubular section of a tubular organ isexcised, resulting in the tubular organ being separated into a firstsegment and a second segment. The end sections of the first and secondsegments are then individually tied in a purse-string fashion,approximated, stapled, and the “purse-stringed” end sections are thencut off. In this full circle resectioning procedure, at least oneseparate invasive incision must be made near the section to be excisedin order to cut and individually tie the separate end sections of theorgan. Also, a separate incision is necessary to place one part of theresectioning device in the first segment and a corresponding second partof the device in the second segment so that the device can then bringthe first and second segments together to re-attach the organ sectionsback together. A first of these separate parts may generally include astaple firing mechanism while the second part includes an anvil forforming the staples. Thus, this type of resectioning procedure involvesthe drawbacks mentioned above in regard to procedures requiring invasiveincisions. In addition, the separation of the organ into two segmentscreates the risk of spillage of non-sterile bowel contents into thesterile body cavity, which can cause severe infection and possiblydeath.

[0007] An alternative resectioning device includes a stapling andcutting assembly on a shaft which can be bent or formed into a desiredshape and then inserted into a patient's body cavity. Once the shaft hasbeen bent into the desired shape, the rigidity of the shaft ensures thatthat shape is maintained throughout the operation. This arrangementlimits the effective operating range of the device as the bending of theshaft into the desired shape before insertion and the rigidity of theshaft once bent require the physician to ascertain the location of theorgan section to be removed before insertion, and deform the shaftaccordingly. Furthermore, the rigidity of the shaft makes it difficultto reach remote areas in the organ—particularly those areas which mustbe reached by a winding and/or circuitous route (e.g., sigmoid colon).Thus, an incision may be required near the organ section to be excisedin order to position the device at the organ section to be excised.

[0008] Currently such FTRD's incorporate standard endoscopes availablefrom various manufacturers. These standard endoscopes are circular inshape, and while a circular shape is desirable in many conventionalapplications where the endoscope is used independently, with FTRD's, acircular endoscope, for example, takes up significant space in the bodylumen. This can result in a sample having a smaller size than desired. Acircular endoscope also may not have sufficient flexibility to bend to adesired location.

SUMMARY OF THE INVENTION

[0009] In accordance with the invention, a proximal housing for afull-thickness resection device (FTRD) is provided with a plurality ofchambers through which fasteners are introduced into a portion of tissueto be resected. The proximal housing has a noncircular cut-out oppositethe plurality of chambers to receive a noncircular endoscope. Theproximal housing also is provided with a resection cavity into which thetissue to be resected is to be received. In addition, shaft openings areprovided through which mounting shafts may be inserted.

[0010] According to another aspect of the invention, the plurality ofchambers is configured so as to provide a substantially ellipticalfastener pattern.

[0011] According to yet another aspect of the invention, the fastenersused are staples.

[0012] According to another aspect of the invention, a noncircularendoscope is also disclosed that is substantially the same shape as thecut-out for insertion into the cut-out whereby the endoscope haspassages to house the functions of remote viewing, lighting,insufflation and irrigation.

[0013] According to another aspect of the invention, the noncircularendoscope is elliptical in shape.

[0014] Additional objects and advantages of the invention will be setforth in part in the description which follows, and in part will beobvious from the description, or may be learned by practice of theinvention. The objects and advantages of the invention will be realizedand attained by means of the elements and combinations particularlypointed out in the appended claims. Both the foregoing generaldescription and the following detailed description are exemplary andexplanatory only and are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings, which are incorporated in andconstitute a part of this specification, illustrate one embodiment ofthe invention and together with the description, serve to explain theprinciples of the invention.

[0016]FIG. 1 is a perspective view showing a full-thickness resectiondevice according to an embodiment of the present invention;

[0017]FIG. 2 is a perspective view showing the device of FIG. 1 mountedon an endoscope according to an embodiment of the present invention;

[0018]FIG. 3 is a perspective view showing the device of FIG. 1 with agrasper mechanism extending therefrom;

[0019]FIG. 4 is a perspective view showing a drive mechanism of FIG. 1;

[0020]FIG. 5 is a perspective view showing the device of FIG. 1 with atapered end for ease of insertion;

[0021]FIG. 6 is a cross-sectional view of a proximal housing of afull-thickness resection device, according to an embodiment of thepresent invention;

[0022]FIG. 7 is a cross-sectional view showing an endoscope to be usedwith the device of FIG. 6.

DESCRIPTION OF THE EMBODIMENTS

[0023] The present invention is directed to a non-circular endoscope andcorresponding FTRD. These non-circular devices have numerous advantagesover existing circular devices. For example, the non-circular shapeallows the device to take up less space within the body lumen into whichit is being inserted. The non-circular endoscope also provides a moreefficient means of packaging the combination of the device andendoscope. The more efficient utilization of space enables a device thatcan capture larger specimen sizes than an equivalent circular endoscopewould permit. In addition, a non-circular endoscope for use with an FTRDmay be more flexible and therefore more easily bend forwards a desiredlocation, due, for example, to the smaller cross-sectional area of theendoscope. In preferred embodiments, the endoscope is shaped forparticular use in combination with devices that perform a full thicknessresection or similar procedure. In addition, the shape of a staplecartridge and anvil of the devices has a more elliptical, non-circularstaple pattern that also provides further advantages.

[0024] Reference will now be made in detail to the present embodimentsof the invention, examples of which is illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts.

[0025] As shown in FIGS. 1 and 2, an FTRD comprises a working headassembly 2 which may be connected to a distal end 4 a of a sheath 4. Theproximal end of the sheath 4 may be connected to a control handle 6. Inoperation, the entire apparatus is mounted onto an endoscope 8, having aproximal end 8 a and a distal end 8 b, by passing the endoscope 8through the control handle 6, the sheath 4, and the working headassembly 2, as shown in FIG. 2. The endoscope 8 is then inserted into abody orifice to locate a lesion in the tubular organ under visualobservation (usually while insufflating the organ). Once the lesion hasbeen located, the working head assembly 2 and the sheath 4 are slidablyadvanced along the endoscope 8 into the tubular organ until the workinghead assembly 2 is in a desired position adjacent to the lesion. Thoseskilled in the art will understand that in an alternative embodiment,the working head assembly 2 may also be detachably coupled to a distalend of the endoscope 8, and the entire arrangement may then be insertedinto the body orifice under visual observation.

[0026] As shown in FIG. 1, the working head assembly 2 comprises ananvil member 10 coupled to a distal end 12 a of a proximal housing 12.The anvil member 10 has a substantially crescent-shaped cross-section(i.e., the outer edge 18 of the anvil member 10 substantially forms aportion of a first ellipse with a second smaller elliptical cut-out 13formed within the first ellipse) with a distal face 16 and a largerproximal face opposite the distal face. The cut-out 13 of the anvilmember 10 is included to allow the endoscope 8 to be slid through theentire working head assembly 2 so that the endoscope 8 may be advancedinto the body passage allowing the working head assembly 2 to later beadvanced into the body to the lesion. In addition, the cut-out 13 alsoprovides forward vision via the endoscope 8. Thus, any shape of thecut-out 13 may be selected which is large enough to accommodate theendoscope 8, with a larger cut-out providing a larger field of vision.An outer surface 18 of the anvil member 10 extends substantiallyparallel to a central axis of the working head assembly 2 while theproximal and distal faces of the anvil member 10 extend in planessubstantially perpendicular to the central axis. The outer surface 18 isjoined to the distal face 16 by a tapered portion 5.

[0027] As shown in FIG. 3, the proximal face of the anvil member 10includes a first cavity 37 and a rim 41 encircling the first cavity 37.A plurality of staple-forming grooves 19 are arranged in two offset rowson the rim 41 of the anvil member 10 and an elliptical guiding slit 21extends radially within the rows of grooves 19. The rim 41 protrudesfrom the remainder of the proximal face so that a shallow cavity isformed on the proximal face.

[0028] The anvil member 10 is coupled to the proximal housing 12 bymeans of two mounting shafts 20 a and 20 b, which may be substantiallycylindrical. Each mounting shaft 20 a, 20 b is coupled to the proximalface 14 of the anvil member 10 on a respective one of two horns 22 a, 22b formed by the crescent-shaped anvil member 10. Although the anvilmember 10 is shown fixedly coupled to the mounting shafts 20 a, 20 b,those skilled in the art will understand that the anvil member 10 mayalso be pivotally coupled to the mounting shafts 20 a, 20 b in order toprovide a greater field of vision through the endoscope 8, as shown inFIG. 3. In this pivoted-type arrangement, the anvil member 10 is angledin a first configuration so that the horns 22 a, 22 b are closer to thedistal end 12 a of the proximal housing than the rest of the anvilmember 10. Then, as the anvil member 10 is drawn towards the distal end12 a of the proximal housing 12, the anvil member 10 would be pressedagainst the distal end 12 a beginning with the horns 22 a, 22 b, whichwould cause the anvil member 10 to pivot until the proximal face 14 ofthe anvil member 10 is parallel to the distal end 12 a.

[0029] As shown in FIG. 1, the mounting shafts 20 a, 20 b are slidablyreceived in mounting holes 26 a, 26 b, which have a size and shapesubstantially corresponding to the size and shape of the mounting shafts20 a, 20 b and which run axially through the proximal housing 12. Themounting shafts 20 a, 20 b are preferably movable axially proximally anddistally within the mounting holes 26 a, 26 b between a proximal mostposition in which a tissue gripping gap of a first predetermined widthis formed between the rim 41 and the distal end 12 a of the proximalhousing 12, and a distal most position in which a tissue receiving gapof a larger second predetermined width is formed between the rim 41 andthe distal end 12 a of the proximal housing 12. The second predeterminedwidth should preferably be more than twice the thickness of a wall ofthe organ being resectioned so that a section of the tubular organ maybe pulled into a resectioning position between the anvil member 10 andthe proximal housing 12.

[0030] As shown in FIG. 4, the proximal end of at least one of themounting shafts 20 a and 20 b is coupled to a drive mechanism 92provided within the proximal housing 12. The drive mechanism 92 iscomposed of a yoke 93 and a drive shaft 95. The yoke 93 is slidablyreceived within the proximal housing 12 for longitudinal movement alongthe axis of the proximal housing 12 so that, when the anvil member 10 isin the proximal most position, the yoke 93 is in a correspondingproximal most position and, when the anvil member is in the distal mostposition, the yoke 93 is in a corresponding distal most position.

[0031] The yoke 93 may be substantially elliptical with a substantiallyrectangular cross-section. Although the ellipse formed by the yoke 93 inFIG. 4 forms substantially a quarter arc of a ellipse, the yoke 93 mayform a larger ellipse based upon the interior accommodations of theproximal housing 12 and the position of the mounting shafts 20 a, 20 b.The mounting shaft 20 a may preferably be coupled to the yoke 93 at afirst end 93 a of the yoke 93, and the mounting shaft 20 b may becoupled at a second end 93 b of the yoke 93. A shaft hole 97, having adiameter substantially corresponding to a diameter of a complementarilythreaded distal end 95 a of the drive shaft 95, extends through the yoke93 at a point substantially midway between the first end 93 a and secondend 93 b. Thus, when the drive shaft 95 is rotated, the threaded distalend 95 a engages the shaft hole 97 to move the yoke 93 proximally ordistally (in dependence upon the direction of rotation of the driveshaft 95).

[0032] The distal end 95 a of the drive shaft 95 should preferably bethreaded over a first section 95 t substantially corresponding in lengthto at least the distance between the proximal and distal most yokepositions, while a remainder portion 95 r may have no threads thereon.The drive shaft 95 may have an increased cross-section in the areasimmediately adjacent to the threaded first section 95 t (proximallyand/or distally of section 95 t), thereby limiting the movement of theyoke 93 to the first section 95 t. Those skilled in the art willunderstand that the drive shaft 95 is rotatably mounted within theproximal housing 12 so that it may only rotated and may not moverelative to the proximal housing 12. The drive shaft 95 extends to aproximal end 95 b which is coupled to a drive cable 90 which extends tothe control handle 6 through the sheath 4. The drive cable 90 may runaxially along the peripheral interior of the sheath 4. Those skilled inthe art will understand that the sheath 4 is torsionally stiff to resistthe torque forces from the drive cables rotating therein. However, thesheath 4 is longitudinally flexible to so that it may be slidablyadvanced along the endoscope 8, while minimizing interference with theoperation of the endoscope 8 and trauma to surrounding tissue. Thesheath 4 is constructed similar to other known endoscope insertiontubes, which are flexible yet allow the transfer of forces to swivel thedistal end of the endoscope 8 in multiple directions and the torqueablerotation of the endoscope.

[0033] In operation, the user advances the endoscope 8, with the workinghead assembly 2 received therearound, to a portion of tissue to beresectioned until the working head assembly 2 is in a desired positionadjacent to the tissue to be resectioned. The user may then apply aforce to the control handle 6 to rotate the drive cable 100, as seen inFIG. 4, which in turn rotates the drive shaft 95 to advance the yoke 93and the anvil member 10 distally away from the distal end 12 a of theproximal housing 12. As shown in FIG. 3 when the anvil member 10 hasreached the distal most position, a known grasping device 98 is advancedthrough the sheath 4 and through the working head assembly 2 to enterthe gap between the anvil member 10 and the distal end 12 a via one ofthe grasper holes 32 and 33. Although the device in FIG. 3 is shownusing a duodenoscope as the endoscope 8, those skilled in the art willunderstand that other types of endoscopes may also be used, such as, forexample, gastroscope, colonoscope, etc.

[0034] As shown in FIG. 1, at least the distal end 12 a of the proximalhousing 12 has a cross-section corresponding in size and shape to theproximal face 14 of the anvil member 10, including a cut-out 29substantially corresponding in size and shape to the cutout 13 of anvilmember 10. The cut-out 29 is provided to receive the endoscope 8 thereinand allow the proximal housing 12 to be slidably advanced along theendoscope 8. Of course, those skilled in the art will understand thatthe shape of the outer surface of the working head assembly 2 may beselected in order to accommodate various desired resectioning shapes,and the shape of the anvil member 10 may preferably be selected to forma continuous surface when positioned adjacent to the proximal housing 12to facilitate advancing the working head assembly to into and removingit from, body passages. It is preferable that the working head assemblyhave a maximum diameter at any point between 15 mm and 40 mm.

[0035] A tissue receiving cavity 30 is formed substantially centrally inthe distal end 12 a of the proximal housing 12 to facilitate the drawingof sections of tubular organs into the gap between the anvil member 10and the distal end 12 a. Those skilled in the art will understand thatthe depth of the cavity 30 may vary depending on the amount of tissue tobe pulled into the cavity 30 and the size of the proximal housing 12.Two grasper holes 32 and 33 extend axially, preferably slightlyoff-center from the longitudinal axis of the proximal housing 12. Thegrasper holes 32 and 33 may each receive a grasping device 108 advancedfrom the control handle 6, through the sheath 4, and through arespective one of the grasper holes 32 and 33.

[0036] In operation, either one or two grasping devices 98 may then beused to pull a section of the tubular organ between the anvil member 10and the distal end 12 a of the proximal housing 12 and into the cavity30. A third grasping device 98 may also be inserted through the workingchannel of the endoscope 8 to provide another means of positioning theorgan section between the anvil member 10 and the proximal housing 12.Of course, those skilled in the art will understand that any desiredinstrument may be advanced to the gap between the anvil member 10 andthe distal end 12 a through any of the grasper holes 32, 33 and theworking channel of the endoscope 8.

[0037] A plurality of staple slits 34 are preferably disposed in twooffset substantially elliptical rows extending along the periphery ofthe distal end 12 a of the proximal housing 12. The staple slits 34extend from an area adjacent to the mounting shaft 26 a to an areaadjacent to the other mounting shaft 26 b. The plurality of staple slits34 may be arranged so that when the anvil member 10 is in the proximalmost position, each of the staple slits 34 is aligned with acorresponding one of the staple-forming grooves 19.

[0038] When the device is configured for operation, a plurality ofstaples is received within the working head assembly 2 with each of thestaples being aligned with a respective one of the staple slits 34. Thestaples are then sequentially fired from the respective staple slits 34by an actuating mechanism (not shown) disposed in the proximal housing12.

[0039] A substantially elliptical blade slit 36 extends substantiallyradially within the staple slits 34 so that, when the anvil is in theproximal most position, the blade slit 36 is aligned with the guidingslit 21 on the anvil member. As shown more clearly in FIG. 4, extensions84 a and 84 b of the blade slit 36 extend into blade housings 74 a and74 b, respectively, which project distally from the distal end 12 a ofproximal housing 12. The blade housings 74 a and 74 b are preferablysituated so that when the anvil member 10 is in its proximal mostposition, the blade housings 74 a and 74 b contact portions 43 a and 43b of the rim 41 of the anvil member 10. The extension of the bladehousings 74 a and 74 b from the proximal housing 12 is preferablyselected so that when the blade housing devices 74 a and 74 b engage theremainder portions 43 a and 43 b of the rim 41 (thereby stopping aproximal movement of the anvil member 10 and defining the proximal mostposition thereof), a gap is formed between the anvil member 10 and thedistal end 12 a of a length sufficient to allow the anvil member 10 tosecurely hold a portion of the organ against the proximal housing 12without crushing and damaging the portion of the organ.

[0040] When positioned at one end of the blade slit 36 (i.e., in one ofthe extensions 84 a and 84 b), a cutting blade (not shown) is preferablycompletely enclosed within the respective one of the blade housingdevices 74 a and 74 b and the guiding slit 21, so that the cutting bladedoes not cut any tissue until the physician intentionally operates theblade. When the physician operates the blade, the blade is driven fromits initial position received within one of the extensions 84 a and 84 baround the blade slit with its cutting edge facing a direction ofmovement, until the blade is received into the other one of theextensions 84 a and 84 b. Thus, after a cutting operation has beenperformed, the blade is once again prevented from inadvertently injuringthe patient.

[0041] As can be seen in the prior art devices utilizing a circularendoscope, the endoscope occupies significant space within the FTRD andalso encroaches upon the resection cavity. With the prior art devices,in order to provide a cavity of the size necessary to perform thedesired surgical procedure, the overall size of the FTRD must be madelarger.

[0042]FIG. 6 shows a cross section of a proximal housing 112 of an FTRD,and is configured to receive a non-circular endoscope within cut-out129. Proximal housing 112 also contains mounting holes 126 a and 126 bas well as mounting shafts.

[0043] As can be seen, cut-out 129 does not extend into cavity 130 asmuch as in the prior art devices, thus allowing the overall size ofproximal housing 112 to be reduced. In addition, the elliptical shape ofthe head provides a more desirable elliptically shaped staple patternfor the staples ejected from chambers 134 than the partial circularpattern of the prior art devices.

[0044] Endoscope 108, as seen in FIG. 7, is an endoscope of the presentembodiment to fit within cut-out 129. Rather than using a standardcircular endoscope of the prior art devices that may provide morechambers than what is necessary for a full-thickness resectionprocedure, the current invention relates to an endoscope that providesonly what is needed for the desired procedure. Endoscope 108 can beprovided with as few as four chambers to house the functions used toperform this procedure: remote viewing, lighting, insufflation andirrigation.

[0045] According to the present embodiment, endoscope 108 has anelliptical shape to fit within cut-out 129 of proximal housing 112.Those skilled in the art would understand that other noncircular shapedendoscopes could be utilized that provide the same low-profile shapethat the elliptical shape provides. Provided within endoscope 108 arefive chambers 108 a-108 e. Chamber 108 c preferably houses the opticsportion of the endoscope. Chambers 108 b and 108 d contain light sourcesto illuminate the area in which the procedure is to be performed.Chambers 108 a and 108 e may provide the insufflation and irrigationfunctions of the endoscope, respectively, although one of ordinary skillin the art could comprehend that these functions may be reversed. Inoperation an FTRD utilizing proximal housing 112 will function in thesame manner as the prior art FTRD's.

[0046] Other embodiments of the invention will be apparent to thoseskilled in the art from consideration of the specification and practiceof the invention disclosed herein. It is intended that the specificationand examples be considered as exemplary only, with a true scope andspirit of the invention being indicated by the following claims.

What is claimed is:
 1. A proximal housing for a full-thickness resectiondevice comprising: a plurality of chambers through which fasteners areintroduced into a portion of tissue to be resected; a noncircularcut-out formed in the proximal housing opposite the plurality ofchambers to receive an endoscope; a resection cavity into which theportion of tissue is to be received; at least one shaft opening throughwhich a mounting shaft may be inserted; and a noncircular endoscope ofsubstantially the same shape as the noncircular cutout inserted intosaid noncircular cut-out.
 2. The proximal housing of claim 1, whereinthe plurality of chambers are configured so as to produce an essentiallyelliptical fastener pattern.
 3. The proximal housing of claim 1, whereinthe noncircular endoscope contains an optical source, at least one lightsource, an insufflation passage and an irrigation passage.
 4. Theproximal housing of claim 1, wherein the fasteners are staples.
 5. Theproximal housing of claim 1, wherein at least one shaft opening includestwo shaft openings.
 6. The proximal housing of claim 1, wherein thenoncircular endoscope is elliptical in shape.
 7. A proximal housing fora full-thickness resection device comprising: a plurality of chambersthrough which fasteners are introduced into a portion of tissue to beresected; a noncircular cut-out formed in the proximal housing oppositethe plurality of chambers to receive an endoscope of noncircular shape;a resection cavity into which the portion of tissue is to be received;and at least one shaft opening through which a mounting shaft may beinserted.
 8. The proximal housing of claim 7, wherein the plurality ofchambers are configured so as to produce an essentially ellipticalfastener pattern.
 9. The proximal housing of claim 7, wherein thefasteners are staples.
 10. The proximal housing of claim 7, wherein atleast one shaft opening includes two shaft openings.
 11. The proximalhousing of claim 7, wherein the noncircular cut-out is elliptical. 12.An endoscope for use in a full-thickness resection device comprising: anoncircular housing; and a plurality of chambers to house the functionsof insufflation, irrigation, lighting and remote viewing.
 13. Theendoscope of claim 12, wherein the housing contains four chambers, oneeach for the functions of insufflation, irrigation, lighting and remoteviewing.
 14. The endoscope of claim 12, wherein the noncircularendoscope is elliptical in shape.